Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP Path: utzoo!utgpu!water!watmath!clyde!rutgers!cbmvax!grr From: grr@cbmvax.UUCP Newsgroups: comp.sys.amiga Subject: Re: making composite video better...? Message-ID: <2652@cbmvax.UUCP> Date: Thu, 29-Oct-87 02:07:18 EST Article-I.D.: cbmvax.2652 Posted: Thu Oct 29 02:07:18 1987 Date-Received: Sat, 31-Oct-87 18:51:44 EST References: <1312@atkins.munsell.UUCP> <2590@cbmvax.UUCP> <1709@charon.unm.edu> <31952@sun.uucp> Reply-To: grr@cbmvax.UUCP (George Robbins) Organization: Commodore Technology, West Chester, PA Lines: 51 In article <31952@sun.uucp> cmcmanis@sun.UUCP (Chuck McManis) writes: > In article <1709@charon.unm.edu> hansb@ariel.UUCP (Hans Bechtel) writes: > > > > I have a commodore 1702 color monitor instead of the regular amiga > > monitor. Currently, I have the composite output of my 1000 going > > through the back of my monitor (and it looks reasonable!) but > > I had heard that you could hook up a cable from the rgb port that > > would provide "proper" (and better) color with a little more clarity. > > How can I build such a cable? > > Where can I get one? > > etc.... To get better output, you would have to modify the composite color encoder circuitry to provide a buffered luminance output. You would then feed this output and the regular composite output into the separate luma and chroma inputs on the 1702 monitor. This should give give better sharpness than regular composite output, but it will still be considerably inferior to a real RGB monitor. > Actually it takes more than a cable, it takes some active circuitry too. > I have found that the composite video from my A1300 GenLock is *lots* > better than the composite video coming out of the machine. All in all > you might be better off taking that route. > > One for Commodore : Any chance that you folks would make a RGB -> Monochrome > adapter that plugs into the A1000 RGB port? I suppose I could buy a 500 and > transfer my files over there, but I really want to know how a tool I wrote > in Hires looks on it's mono output. I've seen what were supposed to be RGB to monochrome conversion cables for the Amiga. I don't know quite how they work or what kind of quality one gets. It probably wouldn't be too hard to put a little switch on the MC1377 video encoder circuitry that would manually disable the color burst and bypass the bandwidth limiting luma delay line. I haven't looked at the chip spec closely, so there might be some problems that would make it more complicated than it appears. The as-is composite color output from the A1000 doesn't look all that bad. You get grey scales and a little more bandwidth/sharpness than on a color monitor. You also get some hatching from the color subcarries, but this actually substitues a textured appearance for the color, It's generally not offensive. Any video hackers out there want to play with this stuff? -- George Robbins - now working for, uucp: {ihnp4|rutgers|allegra}!cbmvax!grr but no way officially representing arpa: out to lunch... Commodore, Engineering Department fone: 215-431-9255 (only by moonlite)